The present invention relates to wireless mobile data networks. More particularly, this invention relates to providing an uninterrupted data stream to a mobile node.
Wireless networks are well known in the prior art and have been around for some time. Wireless networks provide users with data without the need for a wired line tethering the user to a certain location. A wireless network is typically composed of a mobile node, base stations and a supporting infrastructure. The mobile node can be, for example, a cell phone, a PDA or a computer with wireless capabilities. These mobile nodes interact with base stations that transmit and receive data. The base stations may further be connected to a network infrastructure that includes other computers and devices.
One of the features possible with a wireless network is the transmission of a data stream to a mobile node. A data stream may be, for example, music, movies, interactive gaming or television shows. Sending the data individually to each user consumes network bandwidth proportional to the number of users requesting the data stream. A broadcast/multicast service provides the ability to transmit the data stream to multiple users without the need to send the data individually to each user. A user of the mobile node may desire to watch or use the data stream even when roaming. However, the user may encounter a problem when the mobile node switches from one base station to another base station. Most likely, for the data stream to continue uninterrupted as the mobile node moves between the two base stations, the base stations need to simultaneously transmit the same information or the data stream needs to be modified in some way. It is, therefore, desirable to permit the user to enjoy an uninterrupted data stream even while roaming.